soundgen (version 2.3.0)

.audSpectrogram: Auditory spectrogram per sound

Description

Internal soundgen function.

Usage

.audSpectrogram(
  audio,
  step = 1,
  dynamicRange = 80,
  nFilters,
  minFreq = 20,
  maxFreq = audio$samplingRate/2,
  minBandwidth = 1,
  plot = TRUE,
  osc = c("none", "linear", "dB")[2],
  heights = c(3, 1),
  ylim = NULL,
  yScale = c("log", "bark")[2],
  contrast = 0.2,
  brightness = 0,
  maxPoints = c(1e+05, 5e+05),
  padWithSilence = TRUE,
  colorTheme = c("bw", "seewave", "heat.colors", "...")[1],
  extraContour = NULL,
  xlab = NULL,
  ylab = NULL,
  xaxp = NULL,
  mar = c(5.1, 4.1, 4.1, 2),
  main = NULL,
  grid = NULL,
  width = 900,
  height = 500,
  units = "px",
  res = NA,
  ...
)

Arguments

audio

a list returned by readAudio

step

step, ms (determines time resolution). step = NULL means no downsampling at all (ncol of output = length of input audio)

dynamicRange

dynamic range, dB. All values more than one dynamicRange under maximum are treated as zero

nFilters

the number of filters (determines frequency resolution)

minFreq

the range of frequencies to analyze

maxFreq

the range of frequencies to analyze

minBandwidth

minimum filter bandwidth, Hz (otherwise filters may become too narrow when nFilters is high)

plot

should a spectrogram be plotted? TRUE / FALSE

osc

"none" = no oscillogram; "linear" = on the original scale; "dB" = in decibels

heights

a vector of length two specifying the relative height of the spectrogram and the oscillogram (including time axes labels)

ylim

frequency range to plot, kHz (defaults to 0 to Nyquist frequency). NB: still in kHz, even if yScale = bark or mel

yScale

scale of the frequency axis: 'linear' = linear, 'log' = logarithmic (musical), 'bark' = bark with hz2bark, 'mel' = mel with hz2mel

contrast

spectrum is exponentiated by contrast (any real number, recommended -1 to +1). Contrast >0 increases sharpness, <0 decreases sharpness

brightness

how much to "lighten" the image (>0 = lighter, <0 = darker)

maxPoints

the maximum number of "pixels" in the oscillogram (if any) and spectrogram; good for quickly plotting long audio files; defaults to c(1e5, 5e5)

padWithSilence

if TRUE, pads the sound with just enough silence to resolve the edges properly (only the original region is plotted, so the apparent duration doesn't change)

colorTheme

black and white ('bw'), as in seewave package ('seewave'), or any palette from palette such as 'heat.colors', 'cm.colors', etc

extraContour

a vector of arbitrary length scaled in Hz (regardless of yScale!) that will be plotted over the spectrogram (eg pitch contour); can also be a list with extra graphical parameters such as lwd, col, etc. (see examples)

xlab

graphical parameters for plotting

ylab

graphical parameters for plotting

xaxp

graphical parameters for plotting

mar

graphical parameters for plotting

main

graphical parameters for plotting

grid

if numeric, adds n = grid dotted lines per kHz

width

graphical parameters for saving plots passed to png

height

graphical parameters for saving plots passed to png

units

graphical parameters for saving plots passed to png

res

graphical parameters for saving plots passed to png

...

other graphical parameters